I havent tried that exact one, but I have used this one. http://tantusinc.com/catalog/For-Him/Intermediate-C-Ring. Not sure what you mean as far as works? It basically just gives you a raging hard on lol. For me it tends to desensitize my dick a little, but definately keeps you really hard for a lol. I like the silicone ones as opposed to metal, those scare me. I want to be able to get it off in an emergency if i need to since they only recommend using it for max 20 minutes.

well the ring i use doesnt have the perinium messager so i dont know. That being said I've never felt any pleasure messaging my underside/perinium. As far as the 20 minute limit, i guess thats cause essentially you are cutting the blood flow off, and without rich oxygenated blood to flow thru there the cells will start dying and can cause damage. If your lubed up the silicone is pretty easy to get off if your semi hard or limp, but full erection can cause problems if you want it off. If you had to you could cut it off rather quickly with the right tool, with metal, not so much lol.

I want to try the stainless steel one. I have 3 stainless steel rings of varying size...technically I can wear all 3 (base/balls/shaft). If it needs to come off, even erect, a little lube and one ball at a time will do the trick.